/* Shamelessly stolen from weston and modified, original license boiler plate
 * follows.
 */

#if defined(__clang__)
# pragma clang diagnostic ignored "-Wunused-parameter"
#elif (__GNUC__ == 4 && __GNUC_MINOR__ >= 6) || __GNUC__ > 4
# pragma GCC diagnostic ignored "-Wunused-parameter"
#endif


/*
 * Copyright © 2014, 2015 Collabora, Ltd.
 *
 * Permission to use, copy, modify, distribute, and sell this software and
 * its documentation for any purpose is hereby granted without fee, provided
 * that the above copyright notice appear in all copies and that both that
 * copyright notice and this permission notice appear in supporting
 * documentation, and that the name of the copyright holders not be used in
 * advertising or publicity pertaining to distribution of the software
 * without specific, written prior permission.  The copyright holders make
 * no representations about the suitability of this software for any
 * purpose.  It is provided "as is" without express or implied warranty.
 *
 * THE COPYRIGHT HOLDERS DISCLAIM ALL WARRANTIES WITH REGARD TO THIS
 * SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND
 * FITNESS, IN NO EVENT SHALL THE COPYRIGHT HOLDERS BE LIABLE FOR ANY
 * SPECIAL, INDIRECT OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER
 * RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF
 * CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN
 * CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
 */

#define E_COMP_WL
#include "e.h"

#include <sys/mman.h>

#include <assert.h>

#include "linux-dmabuf-unstable-v1-server-protocol.h"

#ifndef DRM_FORMAT_MOD_LINEAR
# define DRM_FORMAT_MOD_LINEAR 0
#endif

void
linux_dmabuf_buffer_ref(struct linux_dmabuf_buffer *buffer)
{
   buffer->refs++;
}

void
linux_dmabuf_buffer_unref(struct linux_dmabuf_buffer *buffer)
{
   int i;

   buffer->refs--;
   if (buffer->refs > 0) return;

   for (i = 0; i < buffer->attributes.n_planes; i++)
     {
        close(buffer->attributes.fd[i]);
        buffer->attributes.fd[i] = -1;
     }

   buffer->attributes.n_planes = 0;
   free(buffer);
}

static void
linux_dmabuf_buffer_destroy(struct linux_dmabuf_buffer *buffer)
{
   linux_dmabuf_buffer_unref(buffer);
}

static void
destroy_params(struct wl_resource *params_resource)
{
   struct linux_dmabuf_buffer *buffer;

   buffer = wl_resource_get_user_data(params_resource);

   if (!buffer) return;

   linux_dmabuf_buffer_destroy(buffer);
}

static void
params_destroy(struct wl_client *client, struct wl_resource *resource)
{
   wl_resource_destroy(resource);
}

static void
params_add(struct wl_client *client, struct wl_resource *params_resource,
	   int32_t name_fd, uint32_t plane_idx, uint32_t offset,
	   uint32_t stride, uint32_t modifier_hi, uint32_t modifier_lo)
{
   struct linux_dmabuf_buffer *buffer;

   buffer = wl_resource_get_user_data(params_resource);
   if (!buffer)
     {
        wl_resource_post_error(params_resource,
                               ZWP_LINUX_BUFFER_PARAMS_V1_ERROR_ALREADY_USED,
                               "params was already used to create a wl_buffer");
        close(name_fd);
        return;
     }

   assert(buffer->params_resource == params_resource);
   assert(!buffer->buffer_resource);

   if (plane_idx >= MAX_DMABUF_PLANES)
     {
        wl_resource_post_error(params_resource,
                               ZWP_LINUX_BUFFER_PARAMS_V1_ERROR_PLANE_IDX,
                               "plane index %u is too high", plane_idx);
        close(name_fd);
        return;
     }

   if (buffer->attributes.fd[plane_idx] != -1)
     {
        wl_resource_post_error(params_resource,
                               ZWP_LINUX_BUFFER_PARAMS_V1_ERROR_PLANE_SET,
                               "a dmabuf has already been added for plane %u",
                               plane_idx);
        close(name_fd);
        return;
     }

   buffer->attributes.fd[plane_idx] = name_fd;
   buffer->attributes.offset[plane_idx] = offset;
   buffer->attributes.stride[plane_idx] = stride;
   if (wl_resource_get_version(params_resource) < ZWP_LINUX_DMABUF_V1_MODIFIER_SINCE_VERSION)
     buffer->attributes.modifier[plane_idx] = DRM_FORMAT_MOD_INVALID;
   else
     {
        buffer->attributes.modifier[plane_idx] =
          ((uint64_t)modifier_hi << 32) | modifier_lo;
     }

   buffer->attributes.n_planes++;
}

static void
linux_dmabuf_wl_buffer_destroy(struct wl_client *client, struct wl_resource *resource)
{
   wl_resource_destroy(resource);
}

static const struct wl_buffer_interface linux_dmabuf_buffer_implementation =
{
   linux_dmabuf_wl_buffer_destroy
};

static void
destroy_linux_dmabuf_wl_buffer(struct wl_resource *resource)
{
   struct linux_dmabuf_buffer *buffer;

   buffer = wl_resource_get_user_data(resource);
   assert(buffer->buffer_resource == resource);
   assert(!buffer->params_resource);

   if (buffer->user_data_destroy_func)
     buffer->user_data_destroy_func(buffer);

   linux_dmabuf_buffer_destroy(buffer);
}

static void
params_create_common(struct wl_client *client, struct wl_resource *params_resource,
		     uint32_t buffer_id, int32_t width, int32_t height,
		     uint32_t format, uint32_t flags)
{
   struct linux_dmabuf_buffer *buffer;
   int i;

   buffer = wl_resource_get_user_data(params_resource);

   if (!buffer)
     {
        wl_resource_post_error(params_resource,
                               ZWP_LINUX_BUFFER_PARAMS_V1_ERROR_ALREADY_USED,
                               "params was already used to create a wl_buffer");
        return;
     }

   assert(buffer->params_resource == params_resource);
   assert(!buffer->buffer_resource);

   /* Switch the linux_dmabuf_buffer object from params resource to
    * eventually wl_buffer resource.
    */
   wl_resource_set_user_data(buffer->params_resource, NULL);
   buffer->params_resource = NULL;

   if (!buffer->attributes.n_planes)
     {
        wl_resource_post_error(params_resource,
                               ZWP_LINUX_BUFFER_PARAMS_V1_ERROR_INCOMPLETE,
                               "no dmabuf has been added to the params");
        goto err_out;
     }

   /* Check for holes in the dmabufs set (e.g. [0, 1, 3]) */
   for (i = 0; i < buffer->attributes.n_planes; i++)
     {
        if (buffer->attributes.fd[i] == -1)
          {
             wl_resource_post_error(params_resource,
                                    ZWP_LINUX_BUFFER_PARAMS_V1_ERROR_INCOMPLETE,
                                    "no dmabuf has been added for plane %i", i);
             goto err_out;
          }
     }

   buffer->attributes.version = 1;
   buffer->attributes.width = width;
   buffer->attributes.height = height;
   buffer->attributes.format = format;
   buffer->attributes.flags = flags;

   if (width < 1 || height < 1)
     {
        wl_resource_post_error(params_resource,
                               ZWP_LINUX_BUFFER_PARAMS_V1_ERROR_INVALID_DIMENSIONS,
                               "invalid width %d or height %d", width, height);
        goto err_out;
     }

   for (i = 0; i < buffer->attributes.n_planes; i++)
     {
        off_t size;

        if ((uint64_t) buffer->attributes.offset[i] + buffer->attributes.stride[i] > UINT32_MAX) {
           wl_resource_post_error(params_resource,
                                  ZWP_LINUX_BUFFER_PARAMS_V1_ERROR_OUT_OF_BOUNDS,
                                  "size overflow for plane %i", i);
           goto err_out;
        }

        if (i == 0 &&
            (uint64_t) buffer->attributes.offset[i] +
            (uint64_t) buffer->attributes.stride[i] * height > UINT32_MAX)
          {
             wl_resource_post_error(params_resource,
                                    ZWP_LINUX_BUFFER_PARAMS_V1_ERROR_OUT_OF_BOUNDS,
                                    "size overflow for plane %i", i);
             goto err_out;
          }

        /* Don't report an error as it might be caused
         * by the kernel not supporting seeking on dmabuf */
        size = lseek(buffer->attributes.fd[i], 0, SEEK_END);
        if (size == -1) continue;

        if (buffer->attributes.offset[i] >= size)
          {
             wl_resource_post_error(params_resource,
                                    ZWP_LINUX_BUFFER_PARAMS_V1_ERROR_OUT_OF_BOUNDS,
                                    "invalid offset %i for plane %i",
                                    buffer->attributes.offset[i], i);
             goto err_out;
          }

        if (buffer->attributes.offset[i] + buffer->attributes.stride[i] > size)
          {
             wl_resource_post_error(params_resource,
                                    ZWP_LINUX_BUFFER_PARAMS_V1_ERROR_OUT_OF_BOUNDS,
                                    "invalid stride %i for plane %i",
                                    buffer->attributes.stride[i], i);
             goto err_out;
          }

        /* Only valid for first plane as other planes might be
         * sub-sampled according to fourcc format */
        if (i == 0 &&
            buffer->attributes.offset[i] + buffer->attributes.stride[i] * height > size)
          {
             wl_resource_post_error(params_resource,
                                    ZWP_LINUX_BUFFER_PARAMS_V1_ERROR_OUT_OF_BOUNDS,
                                    "invalid buffer stride or height for plane %i", i);
             goto err_out;
          }
     }

   /* XXX: Some additional sanity checks could be done with respect
    * to the fourcc format. A centralized collection (kernel or
    * libdrm) would be useful to avoid code duplication for these
    * checks (e.g. drm_format_num_planes).
    */

   if (!e_pixmap_dmabuf_test(buffer)) goto err_failed;

   buffer->buffer_resource =
     wl_resource_create(client, &wl_buffer_interface, 1, buffer_id);
   if (!buffer->buffer_resource)
     {
        wl_resource_post_no_memory(params_resource);
        goto err_buffer;
     }

   wl_resource_set_implementation(buffer->buffer_resource,
                                  &linux_dmabuf_buffer_implementation,
                                  buffer, destroy_linux_dmabuf_wl_buffer);

   /* send 'created' event when the request is not for an immediate
    * import, ie buffer_id is zero */
   if (buffer_id == 0)
     zwp_linux_buffer_params_v1_send_created(params_resource,
                                             buffer->buffer_resource);

   return;

err_buffer:
   if (buffer->user_data_destroy_func) buffer->user_data_destroy_func(buffer);

err_failed:
   if (buffer_id == 0)
     zwp_linux_buffer_params_v1_send_failed(params_resource);
   else
     /* since the behavior is left implementation defined by the
      * protocol in case of create_immed failure due to an unknown cause,
      * we choose to treat it as a fatal error and immediately kill the
      * client instead of creating an invalid handle and waiting for it
      * to be used.
      */
     wl_resource_post_error(params_resource,
                            ZWP_LINUX_BUFFER_PARAMS_V1_ERROR_INVALID_WL_BUFFER,
                            "importing the supplied dmabufs failed");

err_out:
   linux_dmabuf_buffer_destroy(buffer);
}

static void
params_create(struct wl_client *client, struct wl_resource *params_resource,
	      int32_t width, int32_t height, uint32_t format, uint32_t flags)
{
   params_create_common(client, params_resource, 0, width, height, format, flags);
}

static void
params_create_immed(struct wl_client *client, struct wl_resource *params_resource,
		    uint32_t buffer_id, int32_t width, int32_t height,
		    uint32_t format, uint32_t flags)
{
   params_create_common(client, params_resource, buffer_id, width, height,
                        format, flags);
}

static const struct zwp_linux_buffer_params_v1_interface
zwp_linux_buffer_params_implementation =
{
   params_destroy,
   params_add,
   params_create,
   params_create_immed
};

static void
linux_dmabuf_destroy(struct wl_client *client, struct wl_resource *resource)
{
   wl_resource_destroy(resource);
}

static void
linux_dmabuf_create_params(struct wl_client *client,
			   struct wl_resource *linux_dmabuf_resource,
			   uint32_t params_id)
{
   void *compositor;
   struct linux_dmabuf_buffer *buffer;
   uint32_t version;
   int i;

   version = wl_resource_get_version(linux_dmabuf_resource);
   compositor = wl_resource_get_user_data(linux_dmabuf_resource);

   buffer = calloc(1, sizeof *buffer);
   if (!buffer) goto err_out;

   buffer->refs = 1;
   for (i = 0; i < MAX_DMABUF_PLANES; i++)
     buffer->attributes.fd[i] = -1;

   buffer->compositor = compositor;
   buffer->params_resource =
     wl_resource_create(client, &zwp_linux_buffer_params_v1_interface,
                        version, params_id);
   if (!buffer->params_resource)
     goto err_dealloc;

   wl_resource_set_implementation(buffer->params_resource,
                                  &zwp_linux_buffer_params_implementation,
                                  buffer, destroy_params);

   return;

err_dealloc:
   free(buffer);

err_out:
   wl_resource_post_no_memory(linux_dmabuf_resource);
}

/** Get the linux_dmabuf_buffer from a wl_buffer resource
 *
 * If the given wl_buffer resource was created through the linux_dmabuf
 * protocol interface, returns the linux_dmabuf_buffer object. This can
 * be used as a type check for a wl_buffer.
 *
 * \param resource A wl_buffer resource.
 * \return The linux_dmabuf_buffer if it exists, or NULL otherwise.
 */
EINTERN struct linux_dmabuf_buffer *
linux_dmabuf_buffer_get(struct wl_resource *resource)
{
   struct linux_dmabuf_buffer *buffer;

   if (!resource) return NULL;

   if (!wl_resource_instance_of(resource, &wl_buffer_interface,
                                &linux_dmabuf_buffer_implementation))
     return NULL;

   buffer = wl_resource_get_user_data(resource);
   assert(buffer);
   assert(!buffer->params_resource);
   assert(buffer->buffer_resource == resource);

   return buffer;
}

/** Set renderer-private data
 *
 * Set the user data for the linux_dmabuf_buffer. It is invalid to overwrite
 * a non-NULL user data with a new non-NULL pointer. This is meant to
 * protect against renderers fighting over linux_dmabuf_buffer user data
 * ownership.
 *
 * The renderer-private data is usually set from the
 * weston_renderer::import_dmabuf hook.
 *
 * \param buffer The linux_dmabuf_buffer object to set for.
 * \param data The new renderer-private data pointer.
 * \param func Destructor function to be called for the renderer-private
 *             data when the linux_dmabuf_buffer gets destroyed.
 *
 * \sa weston_compositor_import_dmabuf
 */
EINTERN void
linux_dmabuf_buffer_set_user_data(struct linux_dmabuf_buffer *buffer, void *data,
				  dmabuf_user_data_destroy_func func)
{
   assert(data == NULL || buffer->user_data == NULL);

   buffer->user_data = data;
   buffer->user_data_destroy_func = func;
}

/** Get renderer-private data
 *
 * Get the user data from the linux_dmabuf_buffer.
 *
 * \param buffer The linux_dmabuf_buffer to query.
 * \return Renderer-private data pointer.
 *
 * \sa linux_dmabuf_buffer_set_user_data
 */
EINTERN void *
linux_dmabuf_buffer_get_user_data(struct linux_dmabuf_buffer *buffer)
{
   return buffer->user_data;
}

static const struct zwp_linux_dmabuf_v1_interface linux_dmabuf_implementation =
{
   linux_dmabuf_destroy,
   linux_dmabuf_create_params
};

static void
bind_linux_dmabuf(struct wl_client *client, void *data, uint32_t version, uint32_t id)
{
   void *compositor = data;
   struct wl_resource *resource;
   int *formats = NULL;
   uint64_t *modifiers = NULL;
   int num_formats, num_modifiers;
   uint64_t modifier_invalid = DRM_FORMAT_MOD_INVALID;
   int i, j;

   resource =
     wl_resource_create(client, &zwp_linux_dmabuf_v1_interface, version, id);
   if (resource == NULL)
     {
        wl_client_post_no_memory(client);
        return;
     }

   wl_resource_set_implementation(resource, &linux_dmabuf_implementation,
                                  compositor, NULL);

   /*
    * Use EGL_EXT_image_dma_buf_import_modifiers to query and advertise
    * format/modifier codes.
    */
   e_pixmap_dmabuf_formats_query(&formats, &num_formats);

   for (i = 0; i < num_formats; i++)
     {
        e_pixmap_dmabuf_modifiers_query(formats[i], &modifiers, &num_modifiers);

        /* send DRM_FORMAT_MOD_INVALID token when no modifiers are supported
         * for this format */
        if (num_modifiers == 0)
          {
             num_modifiers = 1;
             modifiers = &modifier_invalid;
          }

        for (j = 0; j < num_modifiers; j++)
          {
             if (version >= ZWP_LINUX_DMABUF_V1_MODIFIER_SINCE_VERSION)
               {
                  uint32_t modifier_lo = modifiers[j] & 0xFFFFFFFF;
                  uint32_t modifier_hi = modifiers[j] >> 32;

                  zwp_linux_dmabuf_v1_send_modifier(resource, formats[i],
                                                    modifier_hi,
                                                    modifier_lo);
               }
             else if (modifiers[j] == DRM_FORMAT_MOD_LINEAR ||
                      modifiers == &modifier_invalid)
               {
                  zwp_linux_dmabuf_v1_send_format(resource, formats[i]);
               }
          }
        if (modifiers != &modifier_invalid)
          free(modifiers);
     }
   free(formats);
}

/** Advertise linux_dmabuf support
 *
 * Calling this initializes the zwp_linux_dmabuf protocol support, so that
 * the interface will be advertised to clients. Essentially it creates a
 * global. Do not call this function multiple times in the compositor's
 * lifetime. There is no way to deinit explicitly, globals will be reaped
 * when the wl_display gets destroyed.
 *
 * \param compositor The compositor to init for.
 * \return Zero on success, -1 on failure.
 */
EINTERN int
linux_dmabuf_setup(struct wl_display *display)
{
   if (!wl_global_create(display, &zwp_linux_dmabuf_v1_interface, 3,
                         NULL, bind_linux_dmabuf))
     return -1;

   return 0;
}

/** Resolve an internal compositor error by disconnecting the client.
 *
 * This function is used in cases when the dmabuf-based wl_buffer
 * turns out unusable and there is no fallback path. This is used by
 * renderers which are the fallback path in the first place.
 *
 * It is possible the fault is caused by a compositor bug, the underlying
 * graphics stack bug or normal behaviour, or perhaps a client mistake.
 * In any case, the options are to either composite garbage or nothing,
 * or disconnect the client. This is a helper function for the latter.
 *
 * The error is sent as an INVALID_OBJECT error on the client's wl_display.
 *
 * \param buffer The linux_dmabuf_buffer that is unusable.
 * \param msg A custom error message attached to the protocol error.
 */
EINTERN void
linux_dmabuf_buffer_send_server_error(struct linux_dmabuf_buffer *buffer,
				      const char *msg)
{
   struct wl_client *client;
   struct wl_resource *display_resource;
   uint32_t id;

   assert(buffer->buffer_resource);
   id = wl_resource_get_id(buffer->buffer_resource);
   client = wl_resource_get_client(buffer->buffer_resource);
   display_resource = wl_client_get_object(client, 1);

   assert(display_resource);
   wl_resource_post_error(display_resource, WL_DISPLAY_ERROR_INVALID_OBJECT,
                          "linux_dmabuf server error with "
                          "wl_buffer@%u: %s", id, msg);
}
